ODing on crack

Working from the back forward, I got all the minor cracks in the Viper's hood fixed.  All that I had left was the front end.  I decided to do the repair in four stages, the two corners, the center section, and the front lip.  The previous owner of this car slid the passenger front corner of the nose under something.  When that happened, that corner of the hood was shattered.  I started with the most crunched area, the passenger front corner.  I assumed from the beginning that I would have to redo all of the previous work, but I didn't know just how bad it was until I started grinding away at it.

Almost the moment I started grinding, I started finding poorly laminated "repairs," and layers that weren't really connected to anything.  So I kept grinding.  And grinding.  And grinding.  Even though it had already been "fixed," there were still tons of cracks in the original fiberglass.  Like the previous repairs I've done, I ground out any and all cracks I could find.  I also ground out nearly all of the previous repairs.  Anything of the old repair that I did leave I left strictly as a backing for the new fiberglass I'd be putting in.  You can see just how much of the nose was replaced.  The white is the original panel, the darker color was part of the previous "repair".  Also, there was a block of wood under the "repaired" fiberglass.  Basically, I needed to rebuild the whole corner of the hood.

Ideally, you'd want your new fiberglass to be one big piece.  Because of all the curves and corners on this thing, that is neither practical nor possible.  You will never get a single big sheet of 'glass to go around all those corners and lay down flat.  Trying it will just lead to frustration and more grinding, trust me on this.   The next best thing is overlapping layers of smaller pieces.  Smaller pieces will lay down easier, and go around corners better.  Any time I do fiberglass work, I always plan where and how I'm going to position my pieces before I mix my resin.  I cut and lay my pieces down about where they will be laminated onto the panel, then lift the whole thing off and lay the pieces out on cardboard in the order and approximate location where they will go.  Pre-planning all this before I mix the resin allows for quicker layup, as well as keeps my scissors from getting sticky from cutting 'glass with resin covered gloves.  Here you can see how all the overlapping layers of fiberglass will be placed.

With everything planned out, all I had to do was mix up the resin and lay it up.  The pieces go on one at a time.  Lay a piece of mat on, saturate it with resin, work the bubbles out, and repeat.  Most of the new fiberglass is laminated to 1/4" thick, with many areas being even thicker.  You'll notice the color of the resin is different here.  As I've mentioned before, the Evercoat SMC resin uses standard bondo hardener.  I decided to use blue hardener this time, mostly because I have a big tube of it. 

With that done, I moved onto the other corner.  This corner wasn't nearly as damaged.  It also hadn't actually even been repaired.  Only one crack was "fixed," the rest were left from the accident.  So, like everything else, I ground out all the cracks, and the previous repair material.

Same deal as last time, cut the mat, plan the layers of fiberglass, and add some resin.

The third area I needed to fix was the center section.  This area had a big crack going through it and instead of laying in more actual fiberglass, it was just filled with Kitty Hair(fiberglass reinforced body filler).  Kitty hair in useful for some things, fixing cracks in fiberglass isn't one of them.  So, once again, I ground out the cracks and previous repair material.  This repair also overlaps my previous corner repairs.  Now, fiberglass won't stick very well to shiny surfaces, and cured fiberglass is (relatively) shiny.  Any time you put new 'glass over cured 'glass, you need to grind the shiny off of it.  24 and 36 grit grinding wheels work best.  Even though you don't have interlocking layers, if it's ground back like this the fiberglass should never have delamination issues.  Here you can see the cracks ground out, and my previous repairs ground back so the latest layer of fiberglass will stick.

Same routine, cut, plan, add resin.

The last section to do is the front lip.  I decided to do the front lip as it's own separate section because it has so much damage.  I decided I would just rebuilt the whole front edge.  It's also easier to manage as it's own section, and I wanted to lay it up very thick.  For the new front lip, I decided that the bulk of it would be built from the bottom, and only the outer surface would be rebuilt from the outside.  To do it I ground back all the fiberglass, both old and new, until I just had a very thin edge left to use as a guide/backstop. 

To backfill the lip, I laid in lots of long strips of fiberglass.  All in all, most of the lip ended up being around 1/2" thick.

That's all the fiberglass that needed to be added to the bottom of the hood.  It may not look like much, but to give you a sense of how thick most of the new fiberglass is, I used almost 30 sq/ft of fiberglass mat and 3/4 gallon of resin.